FIELD OF THE INVENTION
[0001] The invention relates to compositions and methods useful in the removal of synthetic
adhesive residues from glass surfaces, such as returnable bottles and similar containers
used in the beverage and food industry. The methods and compositions use lower caustic
compositions to enable lower temperature conditions for the bottle label removal.
The methods of invention remove labels without destruction of the same.
BACKGROUND OF THE INVENTION
[0002] It is common practice in the bottling industry to reuse, recycle, re-wash and refill
returned bottles after consumer use of the item in an effort towards economy in the
industry. Synthetic glues or adhesives are commonly used to affix labels and other
items to surfaces, including bottles. Exemplary disclosures of synthetic glues and
adhesives are provided in
U.S. Patent No. 6,803,085. It is desirable to fully remove soils to clean the bottles as well as remove the
labeling and any remaining adhesive residue left on the surface prior to cleaning,
disinfecting and reuse. Unfortunately, synthetic glues can be difficult to remove
from surfaces such as glass bottles and any incomplete removal presents difficulty
in reusing the item. In addition, conventional removal methods may only partially
remove labels and/or destroy the labels creating additional buildup in the cleaning
solutions (
e.g. partially degraded labels).
[0003] It is known that bottle wash additives and alkaline detergent compositions along
with bottle washing operations may be used to clean returned bottles. Numerous conventional
aqueous-based bottle washing compositions contains caustics, alcohols, nonionic surfactants
and/or other additives. Exemplary disclosures of bottle washing operations include
U.S. Patent No. 2,976,248 titled "Bottle Washing Composition and Method," filed August 1, 1957, and
U.S. Patent No. 6,530,386 titled "Method of Cleaning Returnable Bottles," filed January 25, 2000. However,
such additives and detergents often incompletely remove adhesives and leave residues
or deposits on the surfaces, providing commercially undesirable results. In addition,
commercially-available bottle wash additives often require repeated use to fully remove
residues, utilize harsh cleaning conditions and/or require of large amounts of cleaning
solutions or concentrates, all of which increase the time and cost of bottle washing.
[0004] European Patent Application
1 347 038 A1 describes aqueous compositions containing surfactants, used for removing adhesive
materials from glass surfaces.
[0005] US Patent 4,803,012 discloses cleaning compositions comprising a chelant and a surfactant, used for removing
adhesive labels from bottles in an automatic bottle washing plant. It is therefore
desirable to provide cleaning compositions and methods of use according to the invention
that provide for the complete removal of glues and adhesives. This is a difficult
task to design cleansing compositions and methods for the removal of adhesive substances.
[0006] Accordingly, it is an objective of the claimed invention to develop methods for complete
removal of various types of adhesive materials from glass surfaces, such as adhesive
residue on returnable glass bottles.
[0007] A further object of the invention is novel cleaning compositions for removal of paper
and/or aluminum labels from glass bottles.
[0008] A still further object of the invention is to develop methods for removal of adhesive
labels and residue at reduced temperature and/or caustic levels.
[0009] A still further object of the invention is to develop methods for removal of adhesive
labels without destroying the labels and/or causing pulping. These and other objects
of the invention are illustrated in the description of the invention
BRIEF SUMMARY OF THE INVENTION
[0010] Methods and compositions for complete removal of adhesive material from glass bottles
are provided. The methods and compositions remove labels and adhesive residue using
a preferred solvent system allowing lower temperature and/or caustic conditions. An
advantage of the invention is the complete removal of adhesive residues on bottles,
providing convenient and cost-effective removal. The invention provides advantages
over commercially-available cleaning compositions and methods by both completely removing
bottle labels along with the underlying adhesive residue.
[0011] In an aspect, a method for removing adhesive material from a glass surface includes:
applying a cleaning composition to a glass surface in need of removal of an adhesive
material; and removing said adhesive material from the surface within a period of
time less than 10 minutes, wherein the cleaning composition comprises an aqueous or
non-aqueous basic organic solvent and an amine solvent, a chelant, a surfactant and
less than 25 wt-% sodium hydroxide (caustic), wherein the organic and/or amine solvent
replaces at least a portion of a caustic solution, and wherein the temperature of
the cleaning composition is below 70°C. The adhesive can have one or more layers of
adhesive, laminate and/or other synthetic or natural (e.g. casein) adhesive residue,
and one of more of said layers is a polyacrylic acid or aminocarboxylate. The cleaning
composition can comprise at least one bottle washing additive. The cleaning composition
can have a pH between 2 to 13.5. Further aspects are set out in dependent claims 2-7.
[0012] In a further aspect, a composition for removing adhesive material from a glass surface
includes: an aqueous or non-aqueous basic organic solvent and an amine solvent; a
chelant; at least one surfactant; and less than 25 wt-% sodium hydroxide, as described
in claim 8. The composition effectively removes an adhesive material from a glass
surface at a composition pH between 2 to 13.5 within a period of time less than 10
minutes at temperatures less than 70°C. A further aspect is set out in dependent claim
9. While multiple embodiments are disclosed, still other embodiments of the present
invention will become apparent to those skilled in the art from the following detailed
description, which shows and describes illustrative embodiments of the invention.
Accordingly, the drawings and detailed description are to be regarded as illustrative
in nature and not restrictive.
BRIEF DESCRIPTION OF THE DRAWINGS
[0013]
FIG. 1 shows graphical results of adhesive removal efficacy according to embodiments
of the invention set forth in Example 3.
FIGS. 2-4 show graphical results of adhesive removal efficacy according to embodiments
of the invention set forth in Example 4.
FIGS. 5-10 show graphical results of adhesive removal efficacy according to embodiments
of the invention set forth in Example 5.
FIG. 11 shows graphical results of the synthetic adhesive removal efficacy of compositions
according to the invention as set forth in Example 6.
[0014] Various embodiments of the present invention will be described in detail with reference
to the drawings, wherein like reference numerals represent like parts throughout the
several views. Reference to various embodiments does not limit the scope of the invention.
Figures represented herein are not limitations to the various embodiments according
to the invention and are presented for exemplary illustration of the invention.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT
[0015] The present invention relates to methods and compositions for complete removal of
adhesive material from glass bottles. The compositions and methods of the present
invention have many advantages over conventional bottle washing compositions used
to remove adhesive labels. For example, the methods achieve substantially complete
and/or complete removal of adhesive labels while using lower temperature, less time
and/or lower caustic conditions. An advantage of the invention is the complete removal
of adhesive residues on bottles, providing convenient and cost-effective removal.
The invention provides advantages over commercially-available cleaning compositions
and methods by both completely removing bottle labels along with the underlying adhesive
residue.
[0016] The embodiments of this invention are not limited to particular compositions or methods
for removal of synthetic glue residues from bottle surfaces, which can vary and are
understood by skilled artisans. It is further to be understood that all terminology
used herein is for the purpose of describing particular embodiments only, and is not
intended to be limiting in any manner or scope. For example, as used in this specification
and the appended claims, the singular forms "a," "an" and "the" can include plural
referents unless the content clearly indicates otherwise. Further, all units, prefixes,
and symbols may be denoted in its SI accepted form. Numeric ranges recited within
the specification are inclusive of the numbers defining the range and include each
integer within the defined range.
[0017] So that the present invention may be more readily understood, certain terms are first
defined. Unless defined otherwise, all technical and scientific terms used herein
have the same meaning as commonly understood by one of ordinary skill in the art to
which embodiments of the invention pertain. Many methods and materials similar, modified,
or equivalent to those described herein can be used in the practice of the embodiments
of the present invention without undue experimentation, the preferred materials and
methods are described herein. In describing and claiming the embodiments of the present
invention, the following terminology will be used in accordance with the definitions
set out below.
[0018] The term "about," as used herein, refers to variation in the numerical quantity that
can occur, for example, through typical measuring and liquid handling procedures used
for making concentrates or use solutions in the real world; through inadvertent error
in these procedures; through differences in the manufacture, source, or purity of
the ingredients used to make the compositions or carry out the methods; and the like.
The term "about" also encompasses amounts that differ due to different equilibrium
conditions for a composition resulting from a particular initial mixture. Whether
or not modified by the term "about", the claims include equivalents to the quantities.
[0019] The term "actives" or "percent actives" or "percent by weight actives" or "actives
concentration" are used interchangeably herein and refers to the concentration of
those ingredients involved in cleaning expressed as a percentage minus inert ingredients
such as water or salts.
[0020] The terms "adhesive," "adhesive residue," "glue," and variations thereof, as used
herein, refer to any synthetic adhesive or glue used to adhere a substance to a surface,
namely glass surfaces such as glass bottles with paper labels adhered to its surface.
According to the invention, examples of adhesives include polyacrylic acid adhesives,
or any polymer of a polycarboxylate.
[0021] The term "alkyl" refers to a straight or branched chain monovalent hydrocarbon radical
having a specified number of carbon atoms. Alkyl groups may be unsubstituted or substituted
with substituents that do not interfere with the specified function of the composition
and may be substituted once or twice with the same or different group. Substituents
may include alkoxy, hydroxy, mercapto, amino, alkyl substituted amino, nitro, carboxy,
carbanoyl, carbanoyloxy, cyano, methylsulfonylamino, or halogen, for example. Examples
of "alkyl" include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl,
s-butyl, t-butyl, n-pentyl, n-hexyl, 3-methylpentyl, and the like.
[0022] The term "alkoxy" refers to a straight or branched chain monovalent hydrocarbon radical
having a specified number of carbon atoms and a carbon-oxygen-carbon bond, may be
unsubstituted or substituted with substituents that do not interfere with the specified
function of the composition and may be substituted once or twice with the same or
different group. Substituents may include alkoxy, hydroxy, mercapto, amino, alkyl
substituted amino, nitro, carboxy, carbanoyl, carbanoyloxy, cyano, methylsulfonylamino,
or halogen, for example. Examples include methoxy, ethoxy, propoxy, t-butoxy, and
the like.
[0023] As used herein, the phrase "applied color design" refers to a design, decoration,
decorative element, or label that is applied in a fashion which is intended to be
permanent while the article, for example a bottle, is in circulation, use, and/or
reuse. One type of applied color design is referred to herein as an "applied ceramic
label" (ACL). An applied ceramic label is a label that is applied in a fashion which
is intended to be permanent while the article,
e.g. bottle, is in circulation, use and/or reuse.
[0024] As used herein, the term "substantially free" refers to compositions completely lacking
the component or having such a small amount of the component that the component does
not affect the performance of the composition. The component may be present as an
impurity or as a contaminant and shall be less than 0.5 wt-%. In another embodiment,
the amount of the component is less than 0.1 wt-% and in yet another embodiment, the
amount of component is less than 0.01 wt-%. In a preferred embodiment of the invention
the cleaning compositions are substantially free of caustic and other caustic containing
components (e.g. alkalinity sources), preferably the cleaning compositions are free
of caustic and other caustic containing components.
[0025] The term "substantially similar cleaning performance" refers generally to achievement
by a substitute cleaning product or substitute cleaning system of generally the same
degree (or at least not a significantly lesser degree) of cleanliness or with generally
the same expenditure (or at least not a significantly lesser expenditure) of effort,
or both.
[0026] The term "weight percent," "wt-%," "percent by weight," "% by weight," and variations
thereof, as used herein, refer to the concentration of a substance as the weight of
that substance divided by the total weight of the composition and multiplied by 100.
It is understood that, as used here, "percent," "%," and the like are intended to
be synonymous with "weight percent," "wt-%," etc.
[0027] The methods and compositions of the present invention may comprise, consist essentially
of, or consist of the components and ingredients (or method steps) of the present
invention as well as other components and ingredients (or method steps) described
herein. As used herein, "consisting essentially of" means that the methods and compositions
may include additional steps, components or ingredients, but only if the additional
steps, components or ingredients do not materially alter the basic and novel characteristics
of the claimed methods and compositions.
[0028] While an understanding of the mechanism is not necessary to practice the present
invention and while the present invention is not limited to any particular mechanism
of action, it is contemplated that, in some embodiments the compositions of the invention
and methods of using the same provide significant advantage over commercially-available
bottle wash additives and cleaning methods. According to the invention, both bottle
labels (
e.g. paper and other materials) and underlying adhesive residue are completely removed
without compromising overall bottle cleaning performance and/or creating any pulping
or other residue in the label removal system. Cleaning performance according to the
invention exceeds that of existing commercially-available bottle wash additives that
fail to completely remove adhesive residue from bottles. As a result, the compositions
and methods according to the invention represent a significant advantage in cost savings
and efficiency for industries including recycling and reuse of glass bottles.
[0029] According to the invention, the compositions and methods provide for the complete
removal of synthetic glues and/or adhesives through the use of amines and/or solvents.
The cleaning compositions according to the invention allow the use of lower temperatures,
lower caustic concentrations and reduced time required for the removal of the synthetic
glues and/or adhesives. Although not intending to be limited to a particular theory,
the compositions and methods according to the invention provide chemistry that is
capable of penetrating the synthetic glues and/or adhesives in order to solubilize
the synthetic glues and/or adhesives. The steps of penetrating and solubilizing the
synthetic glues and/or adhesives beneficially allow the complete removal of labels
intact.
Cleaning Compositions
[0030] The cleaning compositions according to the invention are particularly suitable for
various bottle washing applications, including label removal. Beneficially, the cleaning
compositions provide efficient and effective label removal, while reducing the overall
cost of the chemical compositions, reducing the temperature conditions, caustic conditions
and/or mechanical effects required for the label removal and cleaning of the article.
The cleaning compositions according to the invention may comprise, consist of and/or
consist essentially of a solvent. The compositions also include a chelant, a surfactant
and optionally an acidulant, additional solvents and/or other functional ingredients
as set forth herein the description of the invention.
[0031] Various embodiments of the cleaning compositions are shown in Table 1.
TABLE 1
| Component |
Wt-% Ranges |
| Chelant (e.g. Bayhibit, Dequest) |
0.01-20 |
0.1-10 |
1-10 |
| Acidulant (e.g. citric acid, gluconic acid or gluconate) |
0-50 |
0.1-50 |
5-30 |
| Other Solvent |
0-30 |
0-10 |
1-10 |
| Amine Solvent |
0.1-30 |
0.1-10 |
1-10 |
| Surfactant |
0-50 |
5-40 |
10-30 |
| Water Diluent |
10-90 |
10-70 |
20-60 |
| Other Components |
0-20 |
0.1-20 |
1-20 |
[0032] In an aspect of the invention, an acid and base formula is provided that when combined
with a caustic solution forms the salt of the formula to provide a chelating agent.
In a further aspect of the invention, the amine provides a means for effective label
removal from a treated surface.
Solvent
[0033] The compositions according to the invention include a solvent. A solvent or combination
of solvents is useful in the cleaning compositions of the invention to enhance certain
adhesive removal properties. Suitable solvents include water in combination with other
solvents disclosed herein. In some aspects the water is included as a diluent for
the cleaning compositions. The water can include water from any source including deionized
water, tap water, softened water, and combinations thereof.
[0034] In an aspect of the invention, the organic and/or amine solvent replaces at least
a portion of sodium hydroxide (
e.g. caustic). In an aspect, the solvent replaces at least about 10 wt-% sodium hydroxide,
preferably at least about 25 wt-%, at least about 50 wt-%, at least about 75 wt-%,
and most preferably at least about 100 wt-% sodium hydroxide from a cleaning composition.
Without limiting the scope of the invention, the ranges recited are inclusive of the
numbers defining the range and include each integer within the defined range.
[0035] In an aspect, the cleaning compositions of the invention may include non-aqueous
or aqueous solvents which may be alkaline and/or acid solvents. In a preferred aspect,
the solvents are organic molecules. In a further preferred aspect, the solvents are
basic solvents which replace sodium hydroxide solvents conventionally employed in
various bottle washing compositions for label removal.
[0036] Suitable solvents may include organic solvents, such as alcohols or polyols, and
oxygenated solvents, such as lower alkanols, lower alkyl ethers, glycols, aryl glycol
ethers and lower alkyl glycol ethers. Additional examples of useful solvents include
various alcohols, including methanol, ethanol, propanol, isopropanol and butanol,
isobutanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol,
dipropylene glycol, mixed ethylene-propylene glycol ethers, ethylene glycol phenyl
ether, and propylene glycol phenyl ether. Substantially water soluble glycol ether
solvents include propylene glycol methyl ether, propylene glycol propyl ether, dipropylene
glycol methyl ether, tripropylene glycol methyl ether, ethylene glycol butyl ether,
diethylene glycol methyl ether, diethylene glycol butyl ether, ethylene glycol dimethyl
ether, ethylene glycol propyl ether, diethylene glycol ethyl ether, triethylene glycol
methyl ether, triethylene glycol ethyl ether, triethylene glycol butyl ether, and
others.
[0037] "Substantially water soluble" solvents are defined as being infinitely or 100% soluble
by weight in water at 25°C. "Substantially water insoluble" glycol ether solvents
include propylene glycol butyl ether, dipropylene glycol butyl ether, dipropylene
glycol propyl ether, tripropylene glycol butyl ether, dipropylene glycol dimethyl
ether, propylene glycol phenyl ether, ethylene glycol hexyl ether, diethylene glycol
hexyl ether, ethylene glycol phenyl ether, diethylene glycol phenyl ether, and others.
"Substantially water insoluble" solvents are defined as 53% by weight or less of solvent
is soluble in water at 25°C. Preferred solvents are substantially water-soluble solvents.
[0038] For reasons of low cost, commercial availability, and solvent strength, benzyl alcohol
is a preferred solvent. These preferred solvents help reduce surface tension and help
solubilize adhesives.
[0039] The compositions of the invention contain a non-aqueous or aqueous amine solvent.
Suitable amines include, for example, primary, secondary, and/or tertiary amines.
Primary, secondary and/or tertiary amines, include monoamines with C
18 alkyl or alkenyl chains, ethoxylated alkylamines, alkoxylates of ethylenediamine,
imidazoles such as a 1-(2-hydroxyethyl)-2-imidazoline, a 2-alkyl-1-(2-hydroxyethyl)-2-imidazoline,
and the like. Additional amines may include poly sulfonate ammonium salts, as for
example, alkylpoly sulfonate ammonium chloride surfactants such as n-alkyl(C
12-C
18)dimethylbenzyl ammonium chloride, n-tetradecyldimethylbenzylammonium chloride monohydrate,
and a naphthylene-substituted poly sulfonate ammonium chloride such as dimethyl-1-naphthylmethylammonium
chloride.
[0040] Amines may further include diamines carrying at least one nitrogen linked hydrocarbon
group, which represents a saturated or unsaturated linear or branched alkyl group
having at least 10 carbon atoms and preferably 16-24 carbon atoms, or an aryl, aralkyl,
or alkaryl group containing up to 24 carbon atoms, and wherein the optional other
nitrogen linked groups are formed by optionally substituted alkyl groups, aryl group
or aralkyl groups or polyalkoxy groups.
[0041] Amines may also include amine salt such as monoethanolamine, diethanolamine or triethanolamine.
Alkanolamines are also included within the scope of amines useful in combination with
the other ingredients of the cleaning compositions. Typical examples of alkanolamines
include monoethanolamine, monopropanolamine, diethanolamine, dipropanolamine, triethanolamine,
tripropanolamine and the like.
[0042] Amines may also include amino alcohols. Typical examples of amino alcohols include
2-amino-2-methyl-1-propanol, 2-amino-1-butanol, 2-amino-2-methyl-1,3-propanediol,
2-amino-2-ethyl-1,3-propanediol, hydroxymethyl aminomethane, and the like.
[0043] Particularly suitable amines for use in the cleaning compositions include, for example,
triethanolamine, furfurylamine, 4-methylbenzylamine, and Tris[2-(2-methoxyethoxy)-ethyl]
amine.
[0044] According to the method of the invention solvents are typically present at from about
0.01 wt-% to about 80 wt-%, or from about 0.1 wt-% to about 70 wt-%, or from about
1 wt-% to about 60 wt-%. The compositions according to the present invention contain
from 0.1 wt-% to 50 wt-% organic solvent and amine solvent, as defined in claim 8.
Without limiting the scope of the invention, the ranges recited are inclusive of the
numbers defining the range and include each integer within the defined range.
Acidulants
[0045] In some embodiments, the cleaning compositions of the present invention include an
acidulant. As one skilled in the art will ascertain various acidulants may be incorporated
to adjust the pH of the cleaning compositions, including both strong and weak acids
which are not limited according to the invention. In addition, acids may be substituted
with their conjugates (
e.g. gluconic acid or gluconate), which may be employed as "acidulants" herein. In an
aspect of the invention, a sufficient amount of acidulant is included to provide a
composition having a pH from 2 to 13.5, preferably from about 2 to about 13, and more
preferably from about 6 to about 8. In some aspects, the pH approaches a neutral pH
to effectively avoid corrosion of treated surfaces and articles. However, the compositions
according to the invention provide effective adhesion removal at acid pHs as well.
[0046] One skilled in the art will further appreciate that acidulants may be combined with
weak chelants and/or descalants. In some embodiments this would result in neutralized
cleaning compositions.
[0047] According to the invention acidulants are typically present in the compositions in
amounts from about 0 wt-% to about 50 wt-%, or from about 0.1 wt-% to about 50 wt-%,
or from about 5 wt-% to about 30 wt-%. Without limiting the scope of the invention,
the ranges recited are inclusive of the numbers defining the range and include each
integer within the defined range.
Surfactants
[0048] The cleaning compositions of the present invention include a surfactant. Additional
detergency or cleaning efficacy for the cleaning compositions can be obtained from
the use of surfactant materials. Various types of surfactants may be formulated into
the cleaning compositions to enhance the penetration and solubilization of the adhesives
according to the invention, but it is believed that primarily efficacy for the adhesive
removal according to the invention is obtained from the inclusion of the solvents
in the cleaning compositions.
[0049] Surfactants suitable for use with the compositions of the present invention include,
but are not limited to, anionic surfactants, nonionic surfactants, amphoteric surfactants
and cationic surfactants. In some embodiments, the cleaning compositions of the present
invention include 0.1 wt-% to 80 wt-% of a surfactant. In other embodiments the compositions
of the present invention include about 1 wt-% to about 50 wt-% of a surfactant. Without
limiting the scope of the invention, the ranges recited are inclusive of the numbers
defining the range and include each integer within the defined range.
Anionic surfactants
[0050] In some embodiments, the cleaning compositions of the present invention include an
anionic surfactant. Anionic sulfate surfactants suitable for use in the present compositions
include alkyl ether sulfates, alkyl sulfates, the linear and branched primary and
secondary alkyl sulfates, alkyl ethoxysulfates, fatty oleyl glycerol sulfates, alkyl
phenol ethylene oxide ether sulfates, the C
5-C
17 acyl-N-(C
1-C
4 alkyl) and -N-(C
1-C
2 hydroxyalkyl) glucamine sulfates, and sulfates of alkylpolysaccharides such as the
sulfates of alkylpolyglucoside, and the like. Also included are the alkyl sulfates,
alkyl poly(ethyleneoxy) ether sulfates and aromatic poly(ethyleneoxy) sulfates such
as the sulfates or condensation products of ethylene oxide and nonyl phenol (usually
having 1 to 6 oxyethylene groups per molecule).
[0051] Anionic sulfonate surfactants suitable for use in the present compositions also include
alkyl sulfonates, the linear and branched primary and secondary alkyl sulfonates,
and the aromatic sulfonates with or without substituents.
[0052] Anionic carboxylate surfactants suitable for use in the present compositions include
carboxylic acids (and salts), such as alkanoic acids (and alkanoates), ester carboxylic
acids (
e.g. alkyl succinates), ether carboxylic acids, and the like. Such carboxylates include
alkyl ethoxy carboxylates, alkyl aryl ethoxy carboxylates, alkyl polyethoxy polycarboxylate
surfactants and soaps (
e.g. alkyl carboxyls). Secondary carboxylates useful in the present compositions include
those which contain a carboxyl unit connected to a secondary carbon. The secondary
carbon can be in a ring structure,
e.g. as in p-octyl benzoic acid, or as in alkyl-substituted cyclohexyl carboxylates. The
secondary carboxylate surfactants typically contain no ether linkages, no ester linkages
and no hydroxyl groups. Further, they typically lack nitrogen atoms in the head-group
(amphiphilic portion). Suitable secondary soap surfactants typically contain 11-13
total carbon atoms, although more carbons atoms (
e.g., up to 16) can be present. Suitable carboxylates also include acylamino acids (and
salts), such as acylgluamates, acyl peptides, sarcosinates (
e.g. N-acyl sarcosinates), taurates (
e.g. N-acyl taurates and fatty acid amides of methyl tauride), and the like.
[0053] Suitable anionic surfactants include alkyl or alkylaryl ethoxy carboxylates of the
following formula:
R-O-(CH
2CH
2O)
n(CH
2)
m-CO
2X (3)
in which R is a C
8 to C
22 alkyl group or

in which R
1 is a C
4-C
16 alkyl group; n is an integer of 1-20; m is an integer of 1-3; and X is a counter
ion, such as hydrogen, sodium, potassium, lithium, ammonium, or an amine salt such
as monoethanolamine, diethanolamine or triethanolamine. In some embodiments, n is
an integer of 4 to 10 and m is 1. In some embodiments, R is a C
8-C
16 alkyl group. In some embodiments, R is a C
12-C
14 alkyl group, n is 4, and m is 1.
[0054] In other embodiments, R is

and R
1 is a C
6-C
12 alkyl group. In still yet other embodiments, R
1 is a C
9 alkyl group, n is 10 and m is 1.
[0055] Such alkyl and alkylaryl ethoxy carboxylates are commercially available. These ethoxy
carboxylates are typically available as the acid forms, which can be readily converted
to the anionic or salt form. Commercially available carboxylates include, Neodox 23-4,
a C
12-13 alkyl polyethoxy (4) carboxylic acid (Shell Chemical), and Emcol CNP-110, a C
9 alkylaryl polyethoxy (10) carboxylic acid (Witco Chemical). Carboxylates are also
available from Clariant,
e.g. the product Sandopan® DTC, a C
13 alkyl polyethoxy (7) carboxylic acid.
Nonionic Surfactants
[0056] In some embodiments, the cleaning compositions of the present invention include a
nonionic surfactant. Suitable nonionic surfactants suitable for use with the compositions
of the present invention include alkoxylated surfactants. Suitable alkoxylated surfactants
include EO/PO copolymers, capped EO/PO copolymers, alcohol alkoxylates, capped alcohol
alkoxylates, mixtures thereof, or the like. Suitable alkoxylated surfactants for use
as solvents include EO/PO block copolymers, such as the Pluronic and reverse Pluronic
surfactants; alcohol alkoxylates, such as Dehypon LS-54 (R-(EO)
5(PO)
4) and Dehypon LS-36 (R-(EO)
3(PO)
6); and capped alcohol alkoxylates, such as Plurafac LF221 and Tegoten EC11; mixtures
thereof, or the like.
[0057] The semi-polar type of nonionic surface active agents are another class of nonionic
surfactant useful in compositions of the present invention. Semi-polar nonionic surfactants
include the amine oxides, phosphine oxides, sulfoxides and their alkoxylated derivatives.
[0058] Amine oxides are tertiary amine oxides corresponding to the general formula:

wherein the arrow is a conventional representation of a semi-polar bond; and, R
1, R
2, and R
3 may be aliphatic, aromatic, heterocyclic, alicyclic, or combinations thereof. Generally,
for amine oxides of detergent interest, R
1 is an alkyl radical of from about 8 to about 24 carbon atoms; R
2 and R
3 are alkyl or hydroxyalkyl of 1-3 carbon atoms or a mixture thereof; R
2 and R
3 can be attached to each other,
e.g. through an oxygen or nitrogen atom, to form a ring structure; R
4 is an alkylene or a hydroxyalkylene group containing 2 to 3 carbon atoms; and n ranges
from 0 to about 20. An amine oxide can be generated from the corresponding amine and
an oxidizing agent, such as hydrogen peroxide.
[0059] Useful water soluble amine oxide surfactants are selected from the octyl, decyl,
dodecyl, isododecyl, coconut, or tallow alkyl di-(lower alkyl) amine oxides, specific
examples of which are octyldimethylamine oxide, nonyldimethylamine oxide, decyldimethylamine
oxide, undecyldimethylamine oxide, dodecyldimethylamine oxide, iso-dodecyldimethyl
amine oxide, tridecyldimethylamine oxide, tetradecyldimethylamine oxide, pentadecyldimethylamine
oxide, hexadecyldimethylamine oxide, heptadecyldimethylamine oxide, octadecyldimethylaine
oxide, dodecyldipropylamine oxide, tetradecyldipropylamine oxide, hexadecyldipropylamine
oxide, tetradecyldibutylamine oxide, octadecyldibutylamine oxide, bis(2-hydroxyethyl)dodecylamine
oxide, bis(2-hydroxyethyl)-3-dodecoxy-1-hydroxypropylamine oxide, dimethyl-(2-hydroxydodecyl)amine
oxide, 3,6,9-trioctadecyldimethylamine oxide and 3-dodecoxy-2-hydroxypropyldi-(2-hydroxyethyl)amine
oxide.
Amphoteric Surfactants
[0060] In some embodiments, the cleaning compositions of the present invention include an
amphoteric surfactant. Amphoteric, or ampholytic, surfactants contain both a basic
and an acidic hydrophilic group and an organic hydrophobic group. These ionic entities
may be any of anionic or cationic groups described herein for other types of surfactants.
A basic nitrogen and an acidic carboxylate group are the typical functional groups
employed as the basic and acidic hydrophilic groups. In a few surfactants, sulfonate,
sulfate, phosphonate or phosphate provide the negative charge.
[0061] Amphoteric surfactants can be broadly described as derivatives of aliphatic secondary
and tertiary amines, in which the aliphatic radical may be straight chain or branched
and wherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms
and one contains an anionic water solubilizing group,
e.g., carboxy, sulfo, sulfato, phosphato, or phosphono. Amphoteric surfactants are subdivided
into two major classes known to those of skill in the art and described in "
Surfactant Encyclopedia" Cosmetics & Toiletries, Vol. 104 (2) 69-71 (1989), which is incorporated herein by reference in its entirety. The first class includes
acyl/dialkyl ethylenediamine derivatives (
e.g. 2-alkyl hydroxyethyl imidazoline derivatives) and their salts. The second class includes
N-alkylamino acids and their salts. Some amphoteric surfactants can be envisioned
as fitting into both classes.
[0062] Amphoteric surfactants can be synthesized by methods known to those of skill in the
art. For example, 2-alkyl hydroxyethyl imidazoline is synthesized by condensation
and ring closure of a long chain carboxylic acid (or a derivative) with dialkyl ethylenediamine.
Commercial amphoteric surfactants are derivatized by subsequent hydrolysis and ring-opening
of the imidazoline ring by alkylation -- for example with chloroacetic acid or ethyl
acetate. During alkylation, one or two carboxy-alkyl groups react to form a tertiary
amine and an ether linkage with differing alkylating agents yielding different tertiary
amines.
[0063] Long chain imidazole derivatives having application in the present invention generally
have the general formula:

wherein R is an acyclic hydrophobic group containing from about 8 to 18 carbon atoms
and M is a cation to neutralize the charge of the anion, generally sodium. Commercially
prominent imidazoline-derived amphoterics that can be employed in the present compositions
include for example: Cocoamphopropionate, Cocoamphocarboxy-propionate, Cocoamphoglycinate,
Cocoamphocarboxyglycinate, Cocoamphopropyl-sulfonate, and Cocoamphocarboxy-propionic
acid. Amphocarboxylic acids can be produced from fatty imidazolines in which the dicarboxylic
acid functionality of the amphodicarboxylic acid is diacetic acid and/or dipropionic
acid.
[0064] The carboxymethylated compounds (glycinates) described herein above frequently are
called betaines. Betaines are a special class of amphoteric discussed herein below
in the section entitled, Zwitterion Surfactants.
[0065] Long chain N-alkylamino acids are readily prepared by reaction RNH
2, in which R=C
8-C
18 straight or branched chain alkyl, fatty amines with halogenated carboxylic acids.
Alkylation of the primary amino groups of an amino acid leads to secondary and tertiary
amines. Alkyl substituents may have additional amino groups that provide more than
one reactive nitrogen center. Most commercial N-alkylamine acids are alkyl derivatives
of beta-alanine or beta-N(2-carboxyethyl) alanine. Examples of commercial N-alkylamino
acid ampholytes having application in this invention include alkyl beta-amino dipropionates,
RN(C
2H
4COOM)
2 and RNHC
2H
4COOM. In an embodiment, R can be an acyclic hydrophobic group containing from about
8 to about 18 carbon atoms, and M is a cation to neutralize the charge of the anion.
[0066] Suitable amphoteric surfactants include those derived from coconut products such
as coconut oil or coconut fatty acid. Additional suitable coconut derived surfactants
include as part of their structure an ethylenediamine moiety, an alkanolamide moiety,
an amino acid moiety, e.g., glycine, or a combination thereof; and an aliphatic substituent
of from about 8 to 18 (
e.g., 12) carbon atoms. Such a surfactant can also be considered an alkyl amphodicarboxylic
acid. These amphoteric surfactants can include chemical structures represented as:
C
12-alkyl-C(O)-NH-CH
2-CH
2-N
+(CH
2-CH
2-CO
2Na)
2-CH
2-CH
2-OH or C
12-alkyl-C(O)-N(H)-CH
2-CH
2-N
+(CH
2-CO
2Na)
2-CH
2-CH
2-OH. Disodium cocoampho dipropionate is one suitable amphoteric surfactant and is
commercially available under the tradename Miranol™ FBS from Rhodia Inc., Cranbury,
N.J. Another suitable coconut derived amphoteric surfactant with the chemical name
disodium cocoampho diacetate is sold under the tradename Mirataine™ JCHA, also from
Rhodia Inc., Cranbury, N.J.
[0067] A typical listing of amphoteric classes, and species of these surfactants, is given
in
U.S. Patent No. 3,929,678 and in "Surface Active Agents and Detergents" (Vol. I and II by Schwartz, Perry and
Berch).
Cationic Surfactants
[0068] In some embodiments, the cleaning compositions of the present invention include a
cationic surfactant. Cationic surfactants have a positive charge on the hydrotrope
portion of the molecule. Surfactants in which the hydrotrope carries no charge unless
the pH is lowered close to neutrality or lower, but which are then cationic (e.g.
alkyl amines), are also included in this group. In theory, cationic surfactants may
be synthesized from any combination of elements containing an "onium" structure RnX+Y--
and could include compounds other than nitrogen (ammonium) such as phosphorus (phosphonium)
and sulfur (sulfonium). In practice, the cationic surfactant field is dominated by
nitrogen containing compounds, probably because synthetic routes to nitrogenous cationics
are simple and straightforward and give high yields of product, which can make them
less expensive.
[0069] Cationic surfactants preferably include, more preferably refer to, compounds containing
at least one long carbon chain hydrophobic group and at least one positively charged
nitrogen. The long carbon chain group may be attached directly to the nitrogen atom
by simple substitution; or more preferably indirectly by a bridging functional group
or groups in so-called interrupted alkylamines and amido amines. Such functional groups
can make the molecule more hydrophilic and/or more water dispersible, more easily
water solubilized by co-surfactant mixtures, and/or water soluble. For increased water
solubility, additional primary, secondary or tertiary amino groups can be introduced
or the amino nitrogen can be quaternized with low molecular weight alkyl groups. Further,
the nitrogen can be a part of branched or straight chain moiety of varying degrees
of unsaturation or of a saturated or unsaturated heterocyclic ring. In addition, cationic
surfactants may contain complex linkages having more than one cationic nitrogen atom.
[0070] The surfactant compounds classified as amine oxides, amphoterics and zwitterions
are themselves typically cationic in near neutral to acidic pH solutions and can overlap
surfactant classifications. Polyoxyethylated cationic surfactants generally behave
like nonionic surfactants in alkaline solution and like cationic surfactants in acidic
solution.
[0071] The simplest cationic amines, amine salts and quaternary ammonium compounds can be
schematically drawn thus:

in which, R represents a long alkyl chain, R', R", and R'" may be either long alkyl
chains or smaller alkyl or aryl groups or hydrogen and X represents an anion. The
amine salts and quaternary ammonium compounds are preferred for practical use in this
invention due to their high degree of water solubility.
[0072] The majority of large volume commercial cationic surfactants can be subdivided into
four major classes and additional sub-groups known to those or skill in the art and
described in "
Surfactant Encyclopedia", Cosmetics & Toiletries, Vol. 104 (2) 86-96 (1989). The first class includes alkylamines and their salts. The second class includes
alkyl imidazolines. The third class includes ethoxylated amines. The fourth class
includes quaternaries, such as alkylbenzyldimethylammonium salts, alkyl benzene salts,
heterocyclic ammonium salts, tetra alkylammonium salts, and the like. Cationic surfactants
are known to have a variety of properties that can be beneficial in the present compositions.
These desirable properties can include detergency in compositions of or below neutral
pH, antimicrobial efficacy, thickening or gelling in cooperation with other agents,
and the like.
[0073] Cationic surfactants useful in the compositions of the present invention include
those having the formula R
1mR
2xY
LZ wherein each R
1 is an organic group containing a straight or branched alkyl or alkenyl group optionally
substituted with up to three phenyl or hydroxy groups and optionally interrupted by
up to four of the following structures:

or an isomer or mixture of these structures, and which contains from about 8 to 22
carbon atoms. The R
1 groups can additionally contain up to 12 ethoxy groups, m is a number from 1 to 3.
Preferably, no more than one R
1 group in a molecule has 16 or more carbon atoms when m is 2 or more than 12 carbon
atoms when m is 3. Each R
2 is an alkyl or hydroxyalkyl group containing from 1 to 4 carbon atoms or a benzyl
group with no more than one R
2 in a molecule being benzyl, and x is a number from 0 to 11, preferably from 0 to
6. The remainder of any carbon atom positions on the Y group are filled by hydrogens.
Y is can be a group including, but not limited to:

or a mixture thereof. Preferably, L is 1 or 2, with the Y groups being separated by
a moiety selected from R
1 and R
2 analogs (preferably alkylene or alkenylene) having from 1 to about 22 carbon atoms
and two free carbon single bonds when L is 2. Z is a water soluble anion, such as
a halide, sulfate, methylsulfate, hydroxide, or nitrate anion, particularly preferred
being chloride, bromide, iodide, sulfate or methyl sulfate anions, in a number to
give electrical neutrality of the cationic component.
Bottle Washing Additives
[0074] In some embodiments, the cleaning compositions of the present invention include one
or more bottle wash additives. The cleaning compositions may optionally be combined
with bottle washing additives and/or other detergents. The term "bottle washing additive"
and variations thereof, as used herein, refers to surfactants, alkaline and/or acid
sources and cleaning agents employed in bottle washing applications. Exemplary bottle
washing additives are disclosed, for example, in
U.S. Patent No. 7,148,188 titled "Bottlewash Additive Comprising an Alkyl Diphenylene Oxide Disulfonate,".
Additional Functional Ingredients
[0075] Any number of optional ingredients may be added to the cleaning compositions of the
invention. The functional ingredients provide desired properties and functionalities
to the cleaning composition. For the purpose of this application, the term "functional
materials or ingredients" include a material that when dispersed or dissolved in a
use and/or concentrate solution, provides a beneficial property in a particular use.
The cleaning composition may further comprise, consist or consist essentially of a
number of other adjuvants, trace compounds, dispersants, antiredeposition agents,
stabilizing agents, dispersants, defoamers, colorants, rinse aids, catalysts, corrosion
inhibitors, dyes, fragrances, preservatives and other constituents that may be useful
in the invention.
Chelating / Sequestering Agents
[0076] The cleaning compositions of the present invention include a chelating and/or sequestering
agent. Particularly suitable chelating/sequestering agents useful according to the
invention may include, but are not limited to, phosphates, phosphonates, gluconates,
and so forth as disclosed in
U.S. Patent No. 7,148,188. Phosphates suitable for use herein include, but are not limited to, monomers of
phosphoric acid, polymers of phosphoric acid, salts of phosphoric acid or combinations
thereof; ortho phosphates, meta phosphates, tripolyphosphates, or combinations thereof;
phosphoric acid; alkali metal, ammonium and alkanolammonium salts of polyphosphates
(
e.g. sodium tripolyphosphate and other higher linear and cyclic polyphosphate species,
pyrophosphates, and glassy polymeric meta-phosphates); amino phosphates; nitrilotrismethylene
phosphates; and the like; or a combination thereof. Preferred phosphates include phosphoric
acid, and monomers, polymers, and salts thereof, and the like, or a combination thereof.
Suitable phosphonates include a wide variety of phosphonic acids and phosphonate salts,
such as organophosphonates. As used herein, organic phosphonate or organophosphonate
refers to organic phosphonates lacking any amino or imino (
e.g. nitrogen) moieties. The phosphonic acid or phosphonate can include a low molecular
weight phosphonocarboxylic acid such as one having about 2 4 carboxylic acid moieties
and about 3 phosphonic acid groups. Some examples of organic phosphonates include
1-hydroxyethane-1,1-diphosphonic acid; CH
3C(OH)[PO(OH)
2]
2; 1-phosphono-1-methylsuccinic acid, phosphonosuccinic acid; 2-phosphonobutane-1,2,4-tricarboxylic
acid; other similar organic phosphonates; and mixtures thereof. Additional suitable
phosphonates include phosphorous acid, H
3PO
3, and its salts.
[0077] Phosphonic acids can be used in the form of water soluble acid salts, particularly
the alkali metal salts, such as sodium or potassium; the ammonium salts; or the alkylol
amine salts where the alkylol has 2 to 3 carbon atoms, such as mono-, di-, or triethanolamine
salts. Preferred phosphonates include the organic phosphonates. Preferred organic
phosphonates include phosphono butane tricarboxylic acid (PBTC) available from Bayer
Corp. in Pittsburgh Pa. under the tradename of BAYHIBIT™ AM and hydroxy ethylidene
diphosphonic acid (HEDP) such as that sold under the tradename of DEQUEST™ 2010 available
from Monsanto Chemical Co. Additional description of suitable phosphate and phosphonate
sequestrants suitable for use in the invention is described in
U.S. Patent No. 6,436,893.
[0078] The chelating agents/sequestrants may be employed in the cleaning compositions in
amounts from 0.1 wt-% to about 50 wt-%, more suitably about 1 wt-% to about 30 wt-%,
still more preferably from about 3 wt-% to about 10 wt-%. Without limiting the scope
of the invention, the ranges recited are inclusive of the numbers defining the range
and include each integer within the defined range.
Defoaming Agents
[0079] In some embodiments, the cleaning compositions of the present invention include a
defoaming agent. Particularly suitable defoamers may be employed in combination with
surfactants and/or sequestrants. Wetting agents which can be used in the composition
of the invention include any of those constituents known within the art to raise the
surface activity of the composition of the invention. Generally, defoamers which can
be used in accordance with the invention include silica and silicones; aliphatic acids
or esters; alcohols; sulfates or sulfonates; amines or amides; halogenated compounds
such as fluorochlorohydrocarbons; vegetable oils, waxes, mineral oils as well as their
sulfonated or sulfated derivatives; fatty acids and/or their soaps such as alkali,
alkaline earth metal soaps; and phosphates and phosphate esters such as alkyl and
alkaline diphosphates, and tributyl phosphates among others; and mixtures thereof.
[0080] In some embodiments, the cleaning compositions include antifoaming agents or defoamers
which are of food grade quality given the application of the method of the invention.
To this end, one of the more effective antifoaming agents includes silicones. Silicones
such as dimethyl silicone, glycol polysiloxane, methylphenol polysiloxane, trialkyl
or tetralkyl silanes, hydrophobic silica defoamers and mixtures thereof can all be
used in defoaming applications. Commercial defoamers commonly available include silicones
such as Ardefoam® from Armour Industrial Chemical Company which is a silicone bound
in an organic emulsion; Foam Kill® or Kresseo® available from Krusable Chemical Company
which are silicone and non-silicone type defoamers as well as silicone esters; and
Anti-Foam A® and DC-200 from Dow Corning Corporation which are both food grade type
silicones among others. In one embodiment, the defoamer is a block copolymer of polyoxyethylene/polyoxypropylene.
Rinse Aids
[0082] In some embodiments, the cleaning compositions of the present invention include a
rinse aid to improve water drainage/removal from treated surfaces and/or improve drying
of the surface. Generally, rinse aid formulations contain a wetting or sheeting agent
combined with other optional ingredients. The rinse aids are capable of reducing the
surface tension of the rinse water to promote sheeting action and/or to prevent spotting
or streaking caused by beaded water after rinsing is complete. Examples of sheeting
agents include, but are not limited to: polyether compounds prepared from ethylene
oxide, propylene oxide, or a mixture in a homopolymer or block or heteric copolymer
structure. Such polyether compounds are known as polyalkylene oxide polymers, polyoxyalkylene
polymers or polyalkylene glycol polymers. Such sheeting agents require a region of
relative hydrophobicity and a region of relative hydrophilicity to provide surfactant
properties to the molecule. Various additional suitable rinse aids are disclosed for
example in
U.S. Patent Application Serial Nos. 12/706,143 and
13/101,295.
Catalysts
[0083] In some embodiments, the cleaning compositions of the present invention include a
catalyst. Catalysts may be provided in various forms, including for example metallic
manganese, silver, and/or vanadium. In an aspect of the invention, a catalyst preferably
includes at least one source of manganese. In some embodiments, the manganese source
is derived from manganese metal, manganese oxides, colloidal manganese, inorganic
or organic complexes of manganese, including manganese sulfate, manganese carbonate,
manganese acetate, manganese lactate, manganese nitrate, manganese gluconate, manganese
chloride or commercially available as Dragon A350 (also known as Dragon's Blood, available
from Rahu Catalystics of Nottingham, U.K.), or any of the salts of salt forming species
with manganese.
[0084] According to an embodiment, the catalyst includes at least one source of silver.
In some embodiments, the silver source is derived from silver metal, silver oxides,
silver hydroxide, colloidal silver, inorganic or organic complexes of silver, water-soluble
or insoluble silver salts, including silver sulfate, silver carbonate, silver acetate,
silver lactate, silver nitrate, silver gluconate, or silver chloride, or any of the
salts of or salt forming species with silver. According to a still further embodiment,
the catalyst includes at least one source of vanadium.
Composition Formulations
[0086] Compositions for removal of adhesives or synthetic glue residues from a glass surface
are provided according to the invention. The cleaning compositions of the present
invention may be of any suitable form, including liquid, solid (such as tablets, powder/granules),
paste, foam or gel, with powders and tablets. Liquid solutions are preferred according
to the invention and methods of employing the cleaning compositions. The composition
may be in the form of a unit dose product,
i.e. a form which is designed to be used as a single portion of cleaning composition in
a washing operation. Of course, one or more of such single portions may be used in
a cleaning operation.
[0087] The cleaning compositions according to the invention may be provided in the form
of a concentrated composition or a ready to use composition. The concentrated composition
can be referred to more simply as the concentrate, and can be diluted to provide a
ready to use cleaning composition. The ready to use composition can be referred to
as the use composition when it is the composition to be directly applied to a surface
in need of treatment according to the invention. As one skilled in the art will ascertain
the cleaning composition can be provided as a concentrate for purposes of shipment
and the economy of providing cleaning compositions in concentrate formulations. The
concentrate is diluted with water available at the locale or site of dilution. Both
concentrated and diluted ready to use cleaning compositions are encompassed by the
present invention.
[0088] The cleaning compositions of the invention may be made by any suitable method depending
upon their format. Suitable manufacturing methods for the cleaning compositions are
well known in the art.
Methods of Cleaning
[0089] Methods of cleaning employing the cleaning compositions of the invention are included
in the scope of the invention. Use of the cleaning compositions are particularly suitable
for various bottle washing applications, including label removal. Beneficially, the
methods of the invention provide efficient and effective label removal, while reducing
the overall cost of the chemical compositions, reducing the temperature and caustic
conditions and/or mechanical effects required for the label removal and cleaning of
the article.
[0090] Methods according to the invention may comprise, consist of and/or consist essentially
of applying a cleaning composition to a glass surface in need of adhesive removal
and/or cleaning. The methods may further comprise the removal of an adhesive label
from the treated surface.
[0091] As described herein, the invention refers primarily to bottles and the cleaning of
bottles, although a variety of additional containers may be treated according to the
present invention and are encompassed within the scope of the invention.
[0092] A variety of labels may be removed according to the methods of the invention. Suitable
labels include any adhesive-based label. Adhesive-based labels include for example
both paper and metalized labels (
e.g. aluminum), such as those employed on commercially-available returnable glass bottles.
Adhesive-based labels may include synthetic and/or natural adhesives. An example of
a synthetic adhesive is a polyacrylic acid adhesives or polymers of a polycarboxylate.
An example of a natural adhesive is casein or melamine casein.
[0093] In an aspect of the invention, the methods are particularly suited for the removal
of labels, including those that are adhesively applied and have been exposed to the
sun. Adhesively applied labels, after sun exposure, can be extremely difficult to
remove. Beneficially, the step of removing the label from the treated bottle or surface
does not include the destruction of the label itself. In addition, the methods of
the invention do not remove applied color designs from treated surfaces.
[0094] In an aspect of the invention, the removal of a label includes a step of forming
a layer of the cleaning composition over the label and thereafter penetrating the
label to effectuate removal of the label. Without being limited to a particular theory
of the invention, the solvent of the cleaning composition acts to solubilize the adhesive
holding of the label to the surface and/or penetrates the label from the outside (
e.g. top of the label) to create micropores in the label in order to penetrate the label
and thereafter solubilize the adhesive component of the label. In a further aspect
of the invention, the methods include the destabilization of the adhesive layer of
a label. In a further aspect, the removal of aluminum labels does not require a subsequent
step of deflocculation to treat a caustic/aluminum mixture, as a result of the use
of lower caustic cleaning compositions.
[0095] In a further aspect, the label itself that is removed according to the methods of
the invention does not dissolve and/or pulp. As a result of the label being removed
intact it is easily retrievable from a wash source. Beneficially, as the label does
not dissolve and/or pulp the cleaning composition in the wash solution can be used
for an extended period of time in order to minimize waste sources. In a preferred
aspect of the invention, the label itself that is removed further retains the adhesive.
[0096] According to an embodiment of the invention, a cleaning composition comprising a
solvent is applied to a glass surface in need of label removal and/or cleaning. A
use solution may be prepared from the concentrate by diluting the concentrate with
water at a dilution ratio that provides a use solution having desired label-removing
and adhesive-removing properties. The typical dilution factor is between approximately
1 and approximately 10,000 but will depend on factors including the amount and types
of adhesives to be removed, temperatures and the like. In an embodiment, the concentrate
is diluted at a ratio of between about 1:5 and about 1:1,000 concentrate to water.
Particularly, the concentrate is diluted at a ratio of between about 1:5 and about
1:100 concentrate to water.
[0097] Preferably the cleaning composition is provided in a solution in the amounts of from
approximately 0.01 wt-% to about 50 wt-%, preferably from about 0.1 wt-% to about
30 wt-%, more preferably from about 0.6 wt-% to about 10 wt-%. One skilled in the
art may further vary the amount of the concentrated cleaning compositions according
to the invention, depending on the initial concentration of the starting, concentrated
cleaning composition and the desired applications of use thereof. Without limiting
the scope of the invention, the ranges recited are inclusive of the numbers defining
the range and include each integer within the defined range.
[0098] According to an embodiment of the invention, the methods of cleaning include applying
the cleaning composition under a defined pH range within a label removal process and/or
bottle cleaning process. Preferred pH conditions include from 2 to 13.5, preferably
from 2 to 13, more preferably from about 6 to about 8, preferably neutral in order
to avoid corrosion of treated surfaces and articles. Without limiting the scope of
the invention, the ranges recited are inclusive of the numbers defining the range
and include each integer within the defined range. In an aspect of the invention it
is unexpected for the cleaning compositions to remove adhesive labels according to
the methods at an acidic pH. As one skilled in the art will ascertain, adhesive label
removal is conventionally achieved only at alkaline pH using caustic solutions.
[0099] According to a non-limiting embodiment of the invention, the lower pH of cleaning
solutions improves chelation of metal ions and as a result improves the removal of
adhesive residues from the bottles. In an effort to avoid corrosion of the treated
surfaces and articles, corrosion inhibitors may be included in the cleaning compositions
as a result of the use of acidic pHs, including for example corrosion inhibitors disclosed
in
U.S. Serial No. 13/548,367 and
U.S. Patent Nos. 8,343,380,
8,207,102,
8,114,344,
8,114,343,
8,105,531,
8,021,493,
7,960,329,
7,919,448,
7,829,516,
7,828,908,
7,741,262,
7,709,434,
7,196,045,
7,196,044, and
6,835,702.
[0100] According to the methods of using the cleaning compositions, the label removal takes
place under lower temperature conditions in comparison to conventional label removal
methods. The methods include use of the cleaning composition at temperatures below
the conventional temperature range for glass label removal and/or cleaning, which
is below 70°C, preferably below 60°C, more preferably below about 50°C, and still
more preferred at a temperature from about 40-50°C. Without limiting the scope of
the invention, the ranges recited are inclusive of the numbers defining the range
and include each integer within the defined range.
[0101] According to the methods of use of the present invention, lower concentrations of
caustic are used with the cleaning compositions to remove labels from the treated
surface. For example, conventional label removal methods may employ relatively high
concentrations of caustic. According the invention, the cleaning compositions are
employed with caustic concentrations below 25%, more preferably below about 10%. Without
limiting the scope of the invention, the ranges recited are inclusive of the numbers
defining the range and include each integer within the defined range. According to
a preferred embodiment of the invention, the solvent in the cleaning compositions
completely replaces the caustic concentration.
[0102] Beneficially the methods of cleaning according to the invention to remove bottle
labels do not require any increase in time over convention bottle removal methods.
Unexpectedly, despite the use of lower temperatures and less caustic concentrations
and/or no caustic concentration of cleaning components, the methods of label removal
do not require increased time. In some aspects, the methods of the invention achieve
complete label removal in less time that conventional bottle removal methods employing
higher temperature and/or more caustic cleaning compositions. Without being limited
to a particular theory of the invention, the cleaning compositions provided faster
penetration of the label and glue solubilization. In preferred aspects, the methods
provide label removal within less than 5 minutes, most preferably within less than
2 minutes.
[0103] The methods of label removal according to the invention employing the cleaning compositions
may be applied after caustic washing tanks, after any down-line equipment in a bottle
washing process (
e.g. pasteurizer), washing section or any other area. Preferably, the cleaning composition
is applied to a bottle washer wash tank, preferably in a use solution of a weak caustic.
According to an alternative embodiment of the invention, the methods of cleaning include
applying the cleaning composition to a bottle filling line, a tunnel pasteurizer's
water and/or in a rinse section of bottle washer.
[0104] The methods of application of the cleaning compositions may include manual application,
application using a hand operated cleaning equipment, and/or in automatic cleaning
equipment with or without the assistance of mechanical action.
[0105] As one skilled in the art will ascertain, in institutional settings the machines
most often used to convey bottles through an automatic cleaning process include various
zones, such as prerinse or soak, rinse, cleaning, and final rinse.
[0106] The methods of the invention may be practiced with low pressure, no contact cleaning
methods, high pressure scrubbing application of the cleaning compositions, friction
wash with low or high pressure fluid application, presoak cleaning in 'touchless'
and friction-type washes, clean-in-place (closed environment) washing systems, or
any variation of cleaning formats known within the art.
[0107] All publications and patent applications in this specification are indicative of
the level of ordinary skill in the art to which this invention pertains.
EXAMPLES
[0108] Embodiments of the present invention are further defined in the following non-limiting
Examples. It should be understood that these Examples, while indicating certain embodiments
of the invention, are given by way of illustration only. From the above discussion
and these Examples, one skilled in the art can ascertain the essential characteristics
of this invention, and without departing from the scope thereof, can make various
changes and modifications of the embodiments of the invention to adapt it to various
usages and conditions. Thus, various modifications of the embodiments of the invention,
in addition to those shown and described herein, will be apparent to those skilled
in the art from the foregoing description. Such modifications are also intended to
fall within the scope of the appended claims.
[0109] The materials used in the following Examples are provided herein:
Various commercially-available stock solutions were employed in formulations (available
from various sources) including: potassium iodide, citric acid (50%), gluconic acid
(50%), enzymes (e.g. protease)
Glucopon 425N: Alkyl polyglycosides, C8-C14 natural fatty alcohol based, available
from Stepan Company (Northfield, IL)
Ammonyx® LMDO: Lauramidopropylamine/Myristamidopropylamine Oxide, available from Stepan
Company (Northfield, IL)
Bayhibit® AM: Phosphonobutanetricarboxylic acid, available from LANXESS AG (Leverkusen,
Germany, DE)
Dequest® 2010: 1-Hydroxyethylidene-1,1,-diphosphonic acid, HEDP, available from Monsanto
Chemical Co.
Armeen OL: oleylamine, available from Akzo Nobel Surface Chemistry LLC (Chicago, IL)
Rhodiasolv® IRIS and Infinity: dibasic ester solvent, available from Solvay Rhodia
Cola®Solv IES and OES: ionic fluids, available from Colonial Chemical (South Pittsburg,
TN)
Furfuylamine: 2-aminomethylfuran, available from TCI America (Portland, OR)
Tris[2-(2-methoxyethoxy)-ethyl]amine (95%), available from Sigma-Aldrich
Commercial cleaning and floor stripping formulations commercially available from Ecolab
Inc., including for example, Bendurol Maxx, Energy Forte. Neomat S, Neomat Clean and
Neomat C.
Benzyl Alcohol: available from LANXESS AG (Leverkusen, Germany, DE) 4- Methylbenzylamine
EXAMPLE 1
[0110] Various adhesive paper labels used in commercial glass bottling were analyzed to
determine the compositional make-up of the different label adhesives (Optal LG 11
, Colfix s8012 and Turmer Leim ST 50 KF).The labels and adhesives are outlined in
Table 2.
TABLE 2
| Commercial Bottle Label |
Front |
Back |
| Label A |
Alkyl ester, acrylic species |
Cellulose |
| Label B |
Kaolin, ester, alkyl |
Carbonate, alkyl, acrylic, cellulose |
| Label C |
Alkyl ester, acrylic species |
Carbonate, alkyl, acrylic, cellulose |
| |
| Label Adhesive |
| Optal LG 11 |
(Synthetic) Alkyl ester, carboxylic acid salt |
| Colfix S8012 |
(Synthetic) Alkyl ester, carboxylic acid salt |
| Turmer Leim ST 50 KF |
Acrylamide, melamine casein |
[0111] The compositional analysis of the various paper bottle labels and adhesives, including
the functional groups identified, support the use of a polar and/or basic solvent
(
e.g. benzyl alcohol (polar), furfurylamine (basic)) to provide the effective bottle label
removal formulation according to the invention. Namely, the use of the solvent in
a cleaning composition supports the use of lower temperatures and lower caustic concentration
without label destruction in the washer.
EXAMPLE 2
[0112] The labels and adhesives examined in Example 1 were tested under various bottle washing
conditions to determine the efficacy of label removal from glass slides. Each adhesive
and paper label was affixed to a glass slide and the slides were placed, for the amount
of time specified in a 3L glass beaker on a hot place to achieve the specified temperatures
set forth below. The labels were then peeled from the glass slide by hand and the
glass slides were rinsed with cold water. The slides were then visually analyzed to
determine the efficacy of each solution. The greater amount of residues remaining
on the slides indicate a poorer performance.
[0113] Caustic Solution. A 2% NaOH solution was evaluated for label removal performance on the three different
adhesives at 75°C - 80°C for 10 minutes with no agitation. Glue residue remained on
all slides; it was visible as lighter patches on each slide. The 2% NaOH was not as
effective on Optal LG 11 as it was on Colfix S8012 or Turmer Leim ST 50 KF.
[0114] The three commercial adhesives were further tested against various formulations as
set forth in Table 3. The formulations B-E were evaluated in combination with a caustic
solution. 0.25% of each formulation concentrate was combined with the caustic solution.
TABLE 3
| Components |
A |
B |
C |
D |
E |
| Bayhibit AM (50%) |
1.00 |
0.85 |
0.94 |
1.01 |
1.05 |
| Citric acid monohydrate |
5.47 |
4.76 |
6.35 |
5.96 |
5.72 |
| Dequest 2010 |
6.5 |
5.66 |
6.45 |
6.30 |
6.39 |
| Gluconic acid (50%) |
25 |
28.81 |
25.33 |
25.89 |
26.28 |
| Potassium iodide USP |
0.25 |
0.33 |
0.34 |
0.30 |
|
| Glucopon 425N |
|
8.86 |
10.24 |
10.11 |
10.32 |
| Ammonyx LMDO |
|
4.51 |
5.11 |
5.14 |
5.37 |
| Armeen OL |
|
|
|
|
15.65 |
| Furfuylamine |
|
4.57 |
|
|
|
| 4-methyl-benzylamine |
|
|
5.17 |
|
|
| Tris[2-(2-methoxyethoxy)-ethyl] amine |
|
|
|
5.26 |
|
| Benzyl alcohol |
|
4.50 |
5.30 |
5.31 |
7.26 |
| Water |
61.78 |
37.15 |
34.77 |
34.72 |
21.96 |
[0115] The removal of Optal LG 11 adhesive was evaluated using various formulations for
efficacy at a temperature of 50°C for 20 minutes (soak time), without agitation. A
commercial product, Stabilon WTN (Ecolab Inc., St. Paul, MN) (commercial product,
referred to as "A" in Table 2) was evaluated, along with various formulations modified
from formulation A to contain an amine solvent and/or a surfactant according to the
invention. Formulations B, C, D and E are set forth in Table 3 and each contain the
additional component (respectively) furfurylamine, 4-methylbenzylamine, Tris[2-(2-methoxyethoxy)-ethyl]amine,
or Armeen OL. The compositions also include one or more surfactants (
e.g. Glucopon 425N, Ammonyx LMDO, Armeen OL) and an additional solvent benzyl alcohol.
[0116] The modified bottle washing compositions provided improved residue removal in comparison
to formulation A which does not contain the amine solvent, surfactants and/or benzyl
alcohol solvent, demonstrating efficacy of the methods and compositions of the invention.
[0117] The removal of Colfix S8012 adhesive was evaluated using various formulations for
efficacy at a temperature of 50°C for 20 minutes (soak time), without agitation. The
modified bottle washing compositions B, C and D (Table 3) provided improved residue
removal in comparison to a solution of 0.5% NaOH which did not contain the amine and/or
solvent, demonstrating efficacy of the methods and compositions of the invention.
[0118] The removal of Turmer Leim ST 50 KF adhesive was evaluated using various formulations
for efficacy at a temperature of 50°C for 20 minutes (soak time), without agitation.
The modified bottle washing compositions B, C and D (Table 3) provided improved residue
removal in comparison to a solution of 0.5% NaOH which did not contain the amine and/or
solvent, demonstrating efficacy of the methods and compositions of the invention.
EXAMPLE 3
[0119] The efficacy of the cleaning compositions to remove Optical LG 11 adhesive labels
from glass bottles within a shortened period of time was analyzed. Testing of various
formulations at increasing temperatures (from 50°C to 80°C) were conducted to determine
the percentage of area cleaned by a tested solution within 5 minutes using the methods
described in Example 2.
[0120] Various surfactants, solvents and other cleaning agents were screened for efficacy
in adhesive removal according to the methods of the invention. Initially, cleaning
agents screened included: ionic fluids/surfactants Cola®Solv IES and OES; RhodiaSolv
Infinity surfactant; dimethylamionpropylamine solvent; dimethylcyclohexylamine; diethylcyclohexylamine;
1,8-diazobicyclo[5.4.0]undecene-7-ene; tris[2-(2-methoxyethoxy)-ethyl]amine.
[0121] The subsequently evaluated formulations evaluated are shown in Table 4 and described
herein.
TABLE 4
| Components |
F |
G |
H |
I |
J |
K |
L |
| Bayhibit AM (50%) |
1.03 |
6.70 |
1.10 |
1.06 |
1.00 |
1.07 |
|
| Citric acid monohydrate |
4.93 |
5.26 |
4.93 |
4.99 |
5.00 |
5.00 |
|
| Dequest 2010 |
5.96 |
6.56 |
5.96 |
5.12 |
5.13 |
4.93 |
|
| Gluconic acid (50%) |
24.90 |
25.19 |
24.93 |
25.11 |
25.06 |
24.93 |
|
| 2-(2-aminoethoxy) ethanol, DGA |
1.96 |
|
|
|
|
|
|
| Rhodiasolv IRIS |
|
2.00 |
|
|
|
|
|
| Amine solvent (e.g. monoethanolamine, diethanolamine, triethanolamine) |
|
|
1.96 |
2.06 |
2.03 |
|
|
| Urea (50%) |
|
|
|
|
|
3.97 |
98.84 |
| Sodium dioctyl sulfosuccinate |
|
|
|
|
|
|
1.16 |
| Water |
61.22 |
54.28 |
61.13 |
61.66 |
61.78 |
60.10 |
|
[0122] Various additional formulations evaluated using formulated floor care compositions
were also evaluated as shown in Table 5.
TABLE 5
| Components |
M |
N |
O |
P |
| Water Deionized |
50.03 |
70.71 |
51.19 |
68.23 |
| SE21 (10%) |
7.50 |
|
|
|
| Polyquart Ampho 149 |
0.92 |
|
|
|
| Solution of tetrasodium salt of GLDA DRM |
0.75 |
|
|
0.75 |
| Sodium Xylene Sulfonate, 96% |
1.25 |
8.93 |
13.75 |
|
| Sodium Alkane Sulfonate (40%) |
|
|
|
3.92 |
| Palm Kernel FA |
4.84 |
|
|
|
| Tall Oil FA |
18.21 |
|
|
|
| Potassium Hydroxide, 45% |
9.83 |
|
|
8.21 (50%) |
| Sokolan |
4.17 |
|
|
|
| Glucopon 425 |
2.50 |
|
|
|
| Monoethanolamine |
|
4.29 |
1.25 |
0.506 (85%) |
| Methyl glycine diacetic acid |
|
0.71 |
3.7 |
|
| Glycol Phenyl Ether |
|
11.43 |
|
|
| Alcohol Ethoxylate |
|
2.86 |
3.75 |
|
| Decanoic Acid |
|
1.07 |
|
|
| Palmitic acid |
|
|
|
18 |
| Dodecyl benz sulfonic acid |
|
|
3.75 |
|
| Boric acid |
|
|
5 |
|
| Polyether siloxane |
|
|
1.25 |
|
| Dicarobxylic Coconut derivative |
|
|
1.5 |
|
| Lauryl dimethylamine oxide |
|
|
3.75 |
|
| Propylene Glycol |
|
|
5 |
|
| Other (dyes, fragrances, enzymes, diluent, etc.) |
|
|
6.1 |
0.39 |
[0123] The results are shown in Table 6 comparing the temperatures the various formulations
were tested at and the resulting efficacy of label removal (shown as percentage of
area cleaned).

[0124] The screening results show various formulations according to the invention and the
efficacy of removal of the Optigal LG 11 adhesive at various concentrations and temperature
conditions. The results are graphically shown in FIG. 1.
EXAMPLE 4
[0125] Additional label removal testing was conducted at 50°C and 80°C to evaluate the efficacy
of the cleaning compositions to remove Label B (see Table 2) from glass bottles. A
2% NaOH caustic solution was employed with various cleaning compositions according
to the invention provided in the amount of 0.3%. Deionized water was employed. The
adhesives evaluated included casein and synthetic adhesives. The goal of the testing
was to determine cleaning compositions able to completely remove the adhesive label
in the shortest period of time. The tested formulations included formulations A, G,
M, N, O, along with additional commercial products, including Bendurol Maxx, Energy
Forte, Neomat C, and Neomat Clean.
[0126] The results in FIG. 2 show the significantly reduced time required for the casein
adhesive removal from the tested labels, in comparison to the synthetic glue. Beneficially,
the casein was removed in less than 5 minutes by all evaluated formulations at the
lower temperature of 50°C. FIG. 3 again shows the significantly reduced time required
for the casein adhesive removal from the tested labels, in comparison to the synthetic
glue at 80°C. FIG. 4 shows the results of both 50°C and 80°C testing in the single
graph.
EXAMPLE 5
[0127] Additional label removal testing was conducted at 50°C and 80°C using reduced caustic
in various evaluations to determine whether reduced (preferably eliminated caustic)
could be employed for label removal according to the invention. 2% NaOH and 0.5% NaOH
were employed with various cleaning compositions according to the invention along
with a comparison of 0% NaOH (deionized water alone with the formulation) provided
in the amount of 0.3%. Deionized water was employed. The adhesives evaluated included
casein and synthetic adhesives. The tested formulations included formulations F-P.
Visual evaluations were made to determine the amount of the adhesive removed (measured
in accordance with remaining adhesive residue on the glass surface).
[0128] The results in FIG. 5 show the unexpected improvement of the near complete removal
of the adhesive labels using the cleaning compositions in deionized water (free of
caustic). The reduced caustic formulations (at 80°C) also provided improved label
removal using the cleaning composition formulations in comparison to the 2% NaOH caustic
solutions employing the cleaning composition formulations.
[0129] FIGS. 6-9 show additional formulations evaluated at a greater range of temperatures
from 50°C to 80°C. Although some formulations performed better at higher temperatures,
various formulations performed well at the reduced temperatures. FIG. 7 shows the
removal in a reduced caustic solution of 0.5% NaOH. FIG. 8 shows the removal in a
2% NaOH solution employing the various cleaning composition formulations. FIGS. 9-10
show comparisons of the efficacy of the cleaning composition formulations in varying
concentrations of caustic in 80°C and 50°C, respectively.
EXAMPLE 6
[0130] The testing of Example 5 was reevaluated at a temperature of 60°C using the glass
coupons having paper labels affixed with a synthetic glue. The tested formulations
contained either of 0.5% and 2% NaOH and were compared to baseline compositions of
0% NaOH (deionized water alone, shown as "water") and a 2% NaOH control formulation.
The tested formulations according to embodiments of the invention included A, M and
G formulated in either 0.5% or 2% NaOH, with the pH of each composition shown in Table
7.
TABLE 7
| Acidic Solutions |
pH (0.5%) |
pH (2%) |
| G |
3 |
2 |
| A |
3 |
2 |
| |
| Alkaline Solutions |
pH (0.5%) |
pH (2%) |
| M |
8 |
10 |
[0131] The results in FIG. 11 show comparisons of the efficacy of label removal over time
comparing the cleaning composition formulations at both 0.5% and 2% NaOH concentration
at varying temperature conditions and acidity conditions. The results shown that the
formulations A and F performed best with acidic formulations requiring less than 3
minutes for complete removal of the adhesive labels. These results were similar to
the acidic deionized water.
[0132] The results shown in FIG. 11 further suggest that the alkaline formulations have
a negative interaction with synthetic adhesives, as shown by formulation M requiring
a longer period of time to remove the synthetic adhesive. Beneficially, all formulations
outperformed (i.e. reduced adhesive removal time) in comparison to the 2% NaOH (caustic)
formulation. This data clearly shows the impact on removal time (according to the
methods of the invention) for the compositions when removing synthetic glues is dependent
upon the pH of the cleaning solution.
[0133] The inventions being thus described, it will be obvious that the same may be varied
in many ways. Such variations are not to be regarded as a departure from the scope
of the inventions and all such modifications are intended to be included within the
scope of the following claims.